Laser radar and mobile platform

Abstract

A laser radar and a mobile platform, comprising a transmitting tube for transmitting an optical pulse signal; a transmitting driving circuit for controlling the transmitting power of the transmitting tube according to the received driving signal; a receiving tube for receiving the optical pulse signal reflected by an obstacle and converting the received optical pulse signal into an electrical signal; an amplifying circuit for amplifying the electrical signal from the receiving tube; a controller for calculating the distance between the laser radar and the obstacle according to the electrical signal amplified by the amplifying circuit; wherein the amplifying circuit comprises an operational amplifier module and an adjustment module; the adjustment module is used to adjust the amplification factor of the input signal of the amplifying circuit, so that when the energy of the electrical signal from the receiving tube is greater, the amplification factor of the input signal of the amplifying circuit is smaller. Through the laser radar, the amplification factor of the amplifying circuit can be dynamically adjusted according to the energy of the input signal to avoid operational amplifier saturation.

Description

Technical Field

[0001] The present invention relates to the field of circuit technology, and in particular to a laser radar and a mobile platform. Background Art

[0002] In some electronic devices, such as laser radar, signal collection and amplification of the collected signals are often involved. However, the energy of the signal collected by the laser radar usually has a wide range, that is, when the obstacle is close to the laser radar, the energy of the signal obtained by the laser radar through the receiving tube is larger; when the obstacle is far away from the laser radar, the energy of the signal obtained by the receiving tube is smaller. When the electrical signal input to the amplifier circuit is too large, it may cause the operational amplifier of the amplifier circuit to saturate, and saturation will cause distortion of the output signal, thereby affecting the laser radar's measurement of distance; moreover, it takes a certain amount of time for the laser radar to return to normal after saturation, so that the laser radar cannot respond continuously and a measurement blind area is generated. Summary of the invention

[0003] In a first aspect, an embodiment of the present invention provides an amplifier circuit, comprising: an operational amplifier module and an adjustment module; the adjustment module is located at least one of the front-stage circuit, the post-stage circuit or the feedback circuit of the operational amplifier module, and is used to adjust the amplification factor of the input signal of the amplifier circuit, so that the amplifier circuit amplifies the energy of the input signal with the adjusted amplification factor and then outputs it.

[0004] Optionally, the adjustment module adjusts the amplification factor so that when the energy of the input signal of the amplifier circuit is greater than a threshold, the greater the energy of the input signal, the smaller the amplification factor of the input signal by the amplifier circuit.

[0005] Optionally, the adjustment module includes a first clamping module, the first clamping module is located on the front-stage circuit of the operational amplifier module, and the first clamping module is connected to the first input terminal of the operational amplifier module;

[0006] The first clamping module is used to adjust the input signal of the operational amplifier module.

[0007] Optionally, the first clamping module includes a first diode; the first end of the first diode is connected to the first input end of the operational amplifier module; the second end of the first diode is connected to a first reference level; and the input end of the amplifier circuit is connected to the common end of the first end of the first diode and the first input end of the operational amplifier.

[0008] Optionally, the first clamping module includes a first diode and a first resistor; the first end of the first diode is connected to the first input end of the operational amplifier module through the first resistor; the second end of the first diode is connected to a first reference level; and the input end of the amplifier circuit is connected to the first end of the first diode and the common end of the first resistor.

[0009] Optionally, the adjustment module includes a second clamping module; the second clamping module is located on the post-stage circuit of the operational amplifier module, and the second clamping module is connected to the output end of the operational amplifier module;

[0010] The second clamping module is used to adjust the output signal of the operational amplifier module.

[0011] Optionally, the second clamping module includes: a second diode; a first end of the second diode connected to the output end of the operational amplifier module; a second end of the second diode connected to a second reference level; and a common end of the output end of the amplifier circuit connected to the second diode and the output end of the operational amplifier module.

[0012] Optionally, the second clamping module includes: a second diode and a second resistor; the first end of the second diode is connected to the output end of the operational amplifier module through the second resistor; the second end of the second diode is connected to a second reference level; and the output end of the amplifier circuit is connected to a common end of the second diode and the second resistor.

[0013] Optionally, the adjustment module includes a third clamping module, and the third clamping module is located on the feedback circuit of the operational amplifier module; the first input end of the operational amplifier module is connected to the first port of the third clamping module; the second input end of the operational amplifier module is connected to a third reference level; the output end of the amplifier module is connected to the second port of the third clamping module;

[0014] The third clamping module is specifically used to reduce the amplification factor of the input signal of the operational amplifier module by the operational amplifier module when the energy information of the signal input to the operational amplifier module is greater than a first threshold.

[0015] Optionally, the third clamping module includes a third diode; a first end of the third diode is connected to the first input end of the operational amplifier module; and a second end of the third diode is connected to the output end of the operational amplifier module.

[0016] Optionally, the third clamping module includes a third diode and a third resistor; the first end of the third diode is connected to the first input end of the operational amplifier module; the second end of the third diode is connected to the output end of the operational amplifier module; and the third resistor is connected in parallel with the third diode.

[0017] Optionally, the third clamping module includes a third diode, a third resistor, and a fourth resistor; the first end of the third diode is connected to the first input end of the amplifier module through the third resistor, the second end of the third diode is connected to the output end of the operational amplifier module, and the fourth resistor is connected in parallel with the third diode.

[0018] Compared with the prior art, the amplifier circuit provided by the present invention can adjust the amplification factor of the input signal of the amplifier circuit through an adjustment module located in at least one of the front-stage circuit, the post-stage circuit or the feedback circuit of the operational amplifier module, so that the amplifier circuit amplifies the energy of the input signal with the adjusted amplification factor and then outputs it, thereby realizing dynamic adjustment of the amplification factor of the amplifier circuit according to the energy of the input signal.

[0019] In a second aspect, an embodiment of the present invention further provides a laser measuring device, wherein the laser measuring device comprises any amplifying circuit described in the first aspect.

[0020] In a third aspect, an embodiment of the present invention further provides a mobile platform, which includes any laser measuring device described in the second aspect and a platform body, wherein the laser measuring device is installed on the platform body.

[0021] Optionally, the mobile platform includes at least one of an unmanned aerial vehicle, a car and a remote-controlled car.

[0022] In a fourth aspect, an embodiment of the present invention further provides a laser radar, including:

[0023] A transmitting tube, used for transmitting an optical pulse signal;

[0024] A transmitting drive circuit, used for controlling the transmitting power of the transmitting tube according to the received driving signal;

[0025] A receiving tube, used for receiving the optical pulse signal reflected by the obstacle and converting the received optical pulse signal into an electrical signal;

[0026] an amplifier circuit, used for amplifying the electrical signal from the receiving tube;

[0027] A controller, used for calculating the distance between the laser radar and the obstacle according to the electrical signal amplified by the amplifier circuit;

[0028] Wherein, the amplifying circuit includes an operational amplifier module and an adjusting module, the adjusting module includes a first clamping module connected to the first input end of the operational amplifier module, the first clamping module includes a first diode and a first resistor, and one end of the first diode is connected to the first input end of the operational amplifier module through the first resistor;

[0029] The adjustment module is used to adjust the amplification factor of the input signal of the amplifier circuit, wherein when the energy of the electrical signal from the receiving tube is greater than a threshold value, the first diode is turned on to reduce the input signal of the operational amplifier module, so that when the energy of the electrical signal from the receiving tube is greater, the amplification factor of the input signal of the amplifier circuit by the amplifier circuit is smaller.

[0030] Optionally, an input end of the amplifier circuit is connected to a common end of the first diode and the first resistor.

[0031] Optionally, the first clamping module is located on a front-stage circuit of the operational amplifier module.

[0032] Optionally, the adjustment module further includes a second clamping module located on a post-stage circuit of the operational amplifier, wherein the second clamping module is connected to an output end of the operational amplifier and is used to adjust an output signal of the operational amplifier module.

[0033] Optionally, the second clamping module includes a second diode, and when the signal output by the operational amplifier module is greater than a certain value, the second diode is turned on.

[0034] Optionally, the amplification circuit further includes a post-stage operational amplifier connected after the operational amplifier module, and the second diode is used to limit the voltage signal input to the post-stage operational amplifier when turned on, so as to avoid saturation of the post-stage operational amplifier.

[0035] Optionally, the second clamping module further includes a second resistor, and one end of the second diode is connected to the output end of the operational amplifier module through the second resistor.

[0036] Optionally, the adjustment module further includes a third clamping module located on the feedback circuit of the operational amplifier, for reducing the amplification factor of the input signal of the amplifier circuit to the amplifier circuit when the energy information of the signal input to the operational amplifier module is greater than a certain value.

[0037] Optionally, the third clamping module includes a third diode and a fifth resistor, and the third diode is used to be turned on when the energy information of the signal input to the operational amplifier module is greater than a certain value, so as to reduce the amplification factor of the operational amplifier module on the input signal of the operational amplifier module.

[0038] Optionally, the laser radar further includes a comparison circuit and a time-to-digital converter; wherein the comparison circuit is used to convert the signal amplified by the amplifier circuit into a digital pulse signal, and the time-to-digital converter is used to extract the time information of the digital pulse signal and send the time information to the controller;

[0039] The controller is specifically configured to calculate the distance to the obstacle according to the time information.

[0040] In a fifth aspect, an embodiment of the present invention further provides another mobile platform, the mobile platform comprising:

[0041] Lidar; and

[0042] The platform body, the laser radar is installed on the platform body and is used to measure the external environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0044] Figure 1 is a schematic framework diagram of a laser radar provided by an embodiment of the present invention;

[0045] Figure 2 is a schematic framework diagram of an amplifier circuit provided by an embodiment of the present invention;

[0046] Figure 3 is a first wiring diagram of an amplifier circuit provided by an embodiment of the present invention;

[0047] Figure 4 is a second wiring diagram of an amplifier circuit provided by an embodiment of the present invention;

[0048] Figure 5 is a third wiring diagram of an amplifier circuit provided by an embodiment of the present invention;

[0049] Figure 6 is a fourth wiring diagram of an amplifier circuit provided by an embodiment of the present invention;

[0050] Figure 7 is a schematic diagram of the effects of the first clamping module before and after clamping provided by an embodiment of the present invention;

[0051] Figure 8is a fifth wiring diagram of an amplifier circuit provided by an embodiment of the present invention;

[0052] Fig. 9 is a sixth wiring diagram of an amplifier circuit provided by an embodiment of the present invention;

[0053] Fig.10 is a seventh wiring diagram of an amplifier circuit provided by an embodiment of the present invention;

[0054] Fig.11 is a schematic diagram of the effects of the third clamping module before and after clamping provided by an embodiment of the present invention;

[0055] Fig.12 This is an eighth wiring diagram of an amplifier circuit provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0056] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0057] It can be understood that the amplifier circuit provided in each embodiment of the present invention can be applied to a laser measuring device, which can be an electronic device such as a laser radar, a laser ranging device, etc. In one embodiment, the laser measuring device is used to sense external environmental information, such as distance information, angle information, reflection intensity information, speed information, etc. of an environmental target. The laser measuring device can be a laser radar.

[0058] In one embodiment, the laser measuring device of the embodiment of the present invention can be applied to a mobile platform, and the laser measuring device can be installed on the platform body of the mobile platform. The mobile platform with the laser measuring device can measure the external environment, for example, measure the distance between the mobile platform and obstacles for purposes such as obstacle avoidance, and perform two-dimensional or three-dimensional mapping of the external environment. In some embodiments, the mobile platform includes at least one of an unmanned aerial vehicle, a car, and a remote-controlled car. When the laser measuring device is applied to an unmanned aerial vehicle, the platform body is the fuselage of the unmanned aerial vehicle. When the laser measuring device is applied to a car, the platform body is the body of the car. When the laser measuring device is applied to a remote-controlled car, the platform body is the body of the remote-controlled car.

[0059] The following uses a laser radar as an example to describe the amplifier circuit provided by an embodiment of the present invention.

[0060] See also Figure 1 , Figure 1It is a schematic framework diagram of a laser radar provided by an embodiment of the present invention. The laser radar may include: a controller 11, a transmitting drive circuit 12, a transmitting tube 13, a receiving tube 14, an amplifying circuit 15, a comparing circuit 16, a time-to-digital converter (TDC (Time-to-Digital Converter) circuit) 17, etc. The controller 11 can be connected to the transmitting drive circuit 12, the receiving tube 14, the amplifying circuit 15, the comparing circuit 16, the TDC circuit 17, etc. The controller 11 can send a driving signal to the transmitting drive circuit 12. The transmitting drive circuit 12 controls at least one of the transmitting power, the wavelength of the transmitting laser, and the transmitting direction of the transmitting tube 13 according to the received driving signal. It can be understood that the transmitting tube 13 is controlled by the transmitting drive circuit and can emit a light pulse signal in a specific direction. After the light pulse signal emitted by the transmitting tube 13 encounters an obstacle, the obstacle reflects the light pulse signal, and the receiving tube 14 includes a photosensitive sensor for receiving the reflected light pulse signal and converting the received reflected light pulse signal into an electrical signal. The electrical signal can be a voltage signal or a current signal. The receiving tube 14 inputs the converted electrical signal as an input signal to the amplifier circuit 15, which adjusts the input signal and then inputs the adjusted signal to the comparison circuit 16. The comparison circuit 16 is used to convert the amplified signal into a digital pulse signal and input the digital pulse signal to the TDC circuit 17. The TDC circuit 17 extracts the time information contained in the digital pulse signal and sends the time information to the controller 11, which calculates the distance to the obstacle based on the time information.

[0061] See also Figure 2 , Figure 2 is a schematic framework diagram of an amplifier circuit provided by an embodiment of the present invention. Figure 2 As shown, the amplifier circuit may include: an operational amplifier module 21 and an adjustment module 22; the adjustment module 22 is located at least one of the front-stage circuit, the post-stage circuit or the feedback circuit of the operational amplifier module 21, and is used to adjust the amplification factor of the input signal of the amplifier circuit, so that the amplifier circuit amplifies the energy of the input signal with the adjusted amplification factor and then outputs it.

[0062] It can be understood that the amplification factor of the amplifier circuit is equal to the ratio of the output signal of the amplifier circuit to the input signal of the amplifier circuit.

[0063] It can be understood that the adjustment module 22 adjusts the amplification factor so that when the energy of the input signal of the amplifier circuit is greater than a threshold, the greater the energy of the input signal, the smaller the amplification factor of the input signal by the amplifier circuit.

[0064] In the first embodiment of the present invention, the adjustment module 22 includes a first clamping module, which is located on the front-stage circuit of the operational amplifier module 21, and the first clamping module is connected to the first input end of the operational amplifier module 21; the second input end of the operational amplifier module 21 can be connected to the third reference level REF3; the first clamping module is used to adjust the input signal of the operational amplifier module 21 and output the signal through the output end of the operational amplifier module 21.

[0065] Optionally, when the input signal of the amplifier circuit is a voltage signal, the first clamping module may include a first diode. Figure 3 , Figure 3 This is a first wiring diagram of an amplifier circuit provided by an embodiment of the present invention. Figure 3 The connection relationship of the amplifier circuit is explained by taking the operational amplifier module 21 as an operational amplifier IC as an example. Figure 3 As shown, when the voltage signal is a positive voltage signal, the anode of the first diode D1 is connected to the first input terminal of the operational amplifier module 21 (i.e., the reverse input terminal of the operational amplifier IC); the cathode of the first diode D1 is connected to the first reference level REF1; the input signal Uin of the amplifier circuit is input through the common terminal of the anode of the first diode D1 and the reverse input terminal of the operational amplifier IC; the reverse input terminal of the operational amplifier IC is the output terminal Uout of the amplifier circuit. The second input terminal of the operational amplifier module 21 (i.e., the non-inverting input terminal of the operational amplifier IC) is connected to the first reference level REF1.

[0066] When the voltage signal of the input amplifier circuit exceeds the conduction voltage drop of the first diode D1 , the first diode D1 is turned on, thereby limiting the voltage signal of the input operational amplifier module 21 to near the conduction voltage of the first diode D1 , thereby avoiding saturation of the input operational amplifier module 21 .

[0067] It can be understood that when the input signal of the amplifier circuit is a negative voltage signal, the connection mode of the positive and negative electrodes of the first diode is the same as Figure 3 In the amplifier circuit shown, the positive and negative electrodes of the first diode D1 are connected in opposite ways.

[0068] Optionally, when the input signal of the amplifier circuit is a current signal, the first clamping module may include a first diode and a first resistor. Figure 4 , Figure 4 This is a second wiring diagram of an amplifier circuit provided by an embodiment of the present invention. Figure 4 The connection relationship of the amplifier circuit is explained by taking the operational amplifier module 21 as an operational amplifier IC as an example. Figure 4As shown, when the current signal is a positive current signal, the anode of the first diode D1 is connected to the first input terminal of the operational amplifier module 21 (i.e., the reverse input terminal of the operational amplifier IC) through the first resistor R1; the cathode of the first diode D1 is connected to the first reference level REF1; the input signal Uin of the amplifier circuit is input through the anode of the first diode D1 and the common terminal of the first resistor 2212; the reverse input terminal of the operational amplifier IC is the output terminal Uout of the amplifier circuit. The second input terminal of the operational amplifier module 21 (i.e., the non-inverting input terminal of the operational amplifier IC) is connected to the third reference level REF3.

[0069] When the current signal of the input amplifier circuit increases, the voltage drop generated on the first resistor R1 increases. When the voltage drop generated on the first resistor R1 exceeds the conduction voltage drop of the first diode D1, the first diode D1 is turned on, thereby reducing the current signal input to the operational amplifier module 21, thereby avoiding saturation of the input operational amplifier module 21.

[0070] It can be understood that when the input signal of the amplifier circuit is a negative current signal, the connection mode of the positive and negative electrodes of the first diode is the same as Figure 4 In the amplifier circuit shown, the positive and negative electrodes of the first diode D1 are connected in opposite ways.

[0071] In the second embodiment of the present invention, the adjustment module 22 includes a second clamp module; the second clamp module is located on the post-stage circuit of the operational amplifier module 21, and the second clamp module is connected to the output end of the operational amplifier module 21; the second clamp module is used to adjust the output signal of the operational amplifier module 21. It can be understood that the input signal of the amplifier circuit can be input to the first input end of the operational amplifier module; it can also be input to the first input end of the operational amplifier module 21 through the first clamp module; the second input end of the operational amplifier module is connected to the third reference level REF3.

[0072] Optionally, when the input signal of the amplifier circuit is a voltage signal, the second clamping module may include a second diode. Figure 5 , Figure 5 This is a third wiring diagram of an amplifier circuit provided by an embodiment of the present invention. Figure 5 The connection relationship of the amplifier circuit is explained by taking the operational amplifier module 21 as an operational amplifier IC as an example. Figure 5As shown, when the voltage signal is a positive voltage signal, the anode of the second diode D2 is connected to the output end of the operational amplifier module 21 (i.e., the output end of the operational amplifier IC); the cathode of the second diode D2 is connected to the second reference level REF2; the output signal Uout of the amplifier circuit is output from the common end of the second diode D2 and the output end of the operational amplifier IC.

[0073] When the voltage signal of the output amplifier module 21 exceeds the conduction voltage drop of the second diode D2, the second diode D2 is turned on, thereby limiting the voltage signal input to the subsequent operational amplifier to near the conduction voltage of the second diode D2, thereby avoiding saturation of the subsequent operational amplifier.

[0074] It can be understood that when the input signal of the amplifier circuit is a negative voltage signal, the connection mode of the positive and negative electrodes of the second diode is the same as Figure 5 In the amplifier circuit shown, the connection modes of the positive and negative electrodes of the second diode D2 are opposite.

[0075] Optionally, when the input signal of the amplifier circuit is a current signal, the second clamping module may include: a second diode and a second resistor. Figure 6 , Figure 6 This is a fourth wiring diagram of an amplifier circuit provided by an embodiment of the present invention. Figure 6 The connection relationship of the amplifier circuit is explained by taking the operational amplifier module 21 as an operational amplifier IC as an example. Figure 6 As shown, when the current signal is a positive current signal, the anode of the second diode D2 is connected to the output end of the operational amplifier module 21 (i.e., the output end of the operational amplifier IC) through the second resistor R2; the cathode of the second diode D2 is connected to the second reference level REF2; the output signal Uout of the amplifier circuit is output from the common end of the second diode D2 and the second resistor R2.

[0076] When the current signal of the output operational amplifier module 21 increases, the voltage drop across the second resistor R2 increases. When the voltage drop across the second resistor R2 exceeds the conduction voltage drop of the second diode D2, the second diode D2 is turned on, thereby reducing the output current signal to avoid saturation of the operational amplifier.

[0077] It can be understood that when the input signal of the amplifier circuit is a negative current signal, the connection mode of the positive and negative electrodes of the second diode is the same as Figure 6 In the amplifier circuit shown, the connection modes of the positive and negative electrodes of the second diode D2 are opposite.

[0078] Understandably, Figure 5 or Figure 6In the wiring diagram of the amplifier circuit shown, the input signal Uin of the amplifier circuit can be directly input to the first input terminal of the operational amplifier module 21 (ie, the inverting input terminal of the operational amplifier IC), and the non-inverting input terminal of the operational amplifier IC is connected to the third reference level REF3.

[0079] See also Figure 7 , Figure 7 It is a schematic diagram of the effects of the first clamping module before and after clamping provided by an embodiment of the present invention. Figure 7 The solid line in the middle is the actual signal, the dashed straight line represents the on-state voltage of the first diode D1, and the dashed curve represents the signal after clamping. Similarly, the effect of the second clamping module before and after clamping is also as follows: Figure 7 shown.

[0080] In a third embodiment of the present invention, the adjustment module 22 includes a second clamping module; the third clamping module is located on the feedback circuit of the operational amplifier module 21; the first input end of the operational amplifier module 21 is connected to the first port of the third clamping module; the output end of the operational amplifier module 21 is connected to the second port of the third clamping module; the third clamping module is specifically used to: when the energy information of the signal input to the operational amplifier module 21 is greater than the first threshold, reduce the amplification factor of the input signal of the operational amplifier module 21 by the operational amplifier module 21.

[0081] It can be understood that the input signal of the amplifier circuit can be input to the first input end of the operational amplifier module 21; it can also be connected to the first input end of the operational amplifier module 21 through the first clamp module; the second input end of the operational amplifier module 21 can be connected to the third reference level REF3.

[0082] Optionally, the third clamping module may include a third diode and a fifth resistor. Figure 8 , Figure 8 This is a fifth wiring diagram of an amplifier circuit provided by an embodiment of the present invention. Figure 8 The connection relationship of the amplifier circuit is explained by taking the operational amplifier module 21 as an operational amplifier IC as an example. Figure 8 As shown, the anode of the third diode D3 is connected to the first input terminal of the operational amplifier module 21 (i.e., the reverse input terminal of the operational amplifier IC); the cathode of the third diode D3 is connected to the output terminal of the operational amplifier module 21 (i.e., the output terminal of the operational amplifier IC). The second input terminal of the operational amplifier module 21 (i.e., the non-inverting input terminal of the operational amplifier IC) is connected to the third reference level REF3. The input signal Uin of the amplifier circuit can be input to the reverse input terminal of the operational amplifier IC through the fifth resistor R5; the reverse input terminal of the operational amplifier IC is the output terminal Uout of the amplifier circuit.

[0083] When the energy of the signal input to the operational amplifier module 21 is relatively small, the voltage across the third diode D3 is relatively small, the third diode D3 is not turned on, and the resistance RD3 of the third diode is relatively large. At this time, the amplification factor of the operational amplifier module 21 is RD3 / R5, and the operational amplifier module 21 amplifies the signal input to the operational amplifier module 21; when the energy of the signal input to the operational amplifier module 21 is relatively large, the voltage across the third diode D3 is greater than the conduction voltage of the third diode D3, the third diode D3 is turned on, and the resistance RD3 of the third diode is relatively small. At this time, the amplification factor RD3 / R5 of the operational amplifier module 21 is reduced, the energy of the signal output from the operational amplifier module 21 is reduced, and the amplification factor of the amplifier circuit is reduced.

[0084] Optionally, the third clamping module may include a third diode, a third resistor and a fifth resistor. Fig. 9 , Fig. 9 This is a sixth wiring diagram of an amplifier circuit provided by an embodiment of the present invention. Fig. 9 The connection relationship of the amplifier circuit is explained by taking the operational amplifier module 21 as an operational amplifier IC as an example. Fig. 9 As shown, the anode of the third diode D3 is connected to the first input terminal of the operational amplifier module 21 (i.e., the reverse input terminal of the operational amplifier IC); the cathode of the third diode D3 is connected to the output terminal of the operational amplifier module 21 (i.e., the output terminal of the operational amplifier IC); the third resistor R3 is connected in parallel with the third diode D3. The second input terminal of the operational amplifier module 21 (i.e., the non-inverting input terminal of the operational amplifier IC) is connected to the third reference level REF3. The input signal Uin of the amplifier circuit can be input to the reverse input terminal of the operational amplifier IC through the fifth resistor R5; the reverse input terminal of the operational amplifier IC is the output terminal Uout of the amplifier circuit.

[0085] When the energy of the signal input to the operational amplifier module 21 is relatively small, the voltage across the third diode D3 is relatively small, the third diode D3 is not turned on, the resistance RD3 of the third diode D3 is relatively large, and the equivalent resistance Rdc in parallel of the third diode D3 and the third resistor R3 is relatively large. At this time, the amplification factor of the operational amplifier module 21 is Rdc / R5, and the operational amplifier module 21 amplifies the signal input to the operational amplifier module 21; when the energy of the signal input to the operational amplifier module 21 is relatively large, the voltage across the third diode D3 is greater than the conduction voltage of the third diode D3, the third diode D3 is turned on, the resistance RD3 of the third diode is relatively small, and Rdc is reduced. At this time, the amplification factor Rdc / R5 of the operational amplifier module 21 is reduced, the energy of the signal output from the operational amplifier module 21 is reduced, and the amplification factor of the amplifier circuit is reduced.

[0086] Optionally, the third clamping module includes a third diode, a third resistor, a fourth resistor and a fifth resistor; see Fig.10 , Fig.10 This is a seventh wiring diagram of an amplifier circuit provided by an embodiment of the present invention. Fig.10 The connection relationship of the amplifier circuit is explained by taking the operational amplifier module 21 as an operational amplifier IC as an example. Fig.10 As shown, the anode of the third diode D3 is connected to the first input terminal of the operational amplifier module 21 through the third resistor R3, the cathode of the third diode D3 is connected to the output terminal of the operational amplifier module 21, and the fourth resistor R4 is connected in parallel with the third diode D3. The second input terminal of the operational amplifier module 21 (i.e., the same-direction input terminal of the operational amplifier IC) is connected to the third reference level REF3. The input signal Uin of the amplifier circuit can be input to the reverse input terminal of the operational amplifier IC through the fifth resistor R5; the reverse input terminal of the operational amplifier IC is the output terminal Uout of the amplifier circuit.

[0087] When the energy of the signal input to the operational amplifier module 21 is relatively small, the voltage across the third diode D3 is relatively small, the third diode D3 is not turned on, the resistance RD3 of the third diode D3 is relatively large, the equivalent resistance Rdc in parallel with the third resistor R4 connected in series with R3 is relatively large, at this time, the amplification factor of the operational amplifier module 21 is Rdc / R5, and the operational amplifier module 21 amplifies the signal input to the operational amplifier module 21; when the energy of the signal input to the operational amplifier module 21 is relatively large, the voltage across the third diode D3 is greater than the conduction voltage of the third diode D3, the third diode D3 is turned on, the resistance RD3 of the third diode is relatively small, and Rdc is reduced, at this time, the amplification factor Rdc / R5 of the operational amplifier module 21 is reduced, the energy of the signal output from the operational amplifier module 21 is reduced, and the amplification factor of the amplifier circuit is reduced.

[0088] It should be noted that in Figure 8 , Fig. 9 as well as Fig.10 In the illustrated embodiment, the fifth resistor R5 is not a necessary component of the third clamping module. For an operational amplifier IC with stable operational amplifier, the input signal Uin of the amplifier circuit can also be directly input to the inverting input terminal of the operational amplifier IC.

[0089] Understandably, Figure 8 , Fig. 9 as well as Fig.10 In the embodiment shown, the input signal of the amplifier circuit is a positive current signal or a positive voltage signal. When the input signal of the amplifier circuit is a negative voltage signal or a negative current signal, the connection modes of the positive and negative electrodes of the third diode are respectively the same as Figure 8 , Fig. 9 as well as Fig.10 In the amplifier circuit shown, the connection modes of the positive and negative electrodes of the third diode D3 are opposite.

[0090] See also Fig.11 , Fig.11 It is a schematic diagram of the effects before and after clamping of the third clamping module provided by an embodiment of the present invention. Fig.11 The solid line in the middle is the actual signal, and the dotted line is the signal after clamping. When the signal energy is small, such as Fig.11 As shown in the right curve, the third clamping module amplifies the input signal; when the signal energy is large, such as Fig.12 As shown by the right curve, the amplification factor of the operational amplifier module 21 is reduced so that its output signal does not exceed the conduction voltage of the third diode D3.

[0091] In the fourth embodiment of the present invention, the amplifier circuit may include a first clamping module, a second clamping module and a third clamping module. Fig.12 , Fig.12 This is an eighth wiring diagram of an amplifier circuit provided by an embodiment of the present invention. For detailed description, please refer to the relevant descriptions of the first clamping module, the second clamping module and the third clamping module, which will not be repeated here.

[0092] It should be noted that the first diode D1 in the first clamping module and the second diode D2 in the second clamping module may also be a Zener diode or a TVS diode. In this case, the conduction voltage of the diode is the breakdown voltage of the Zener diode or the TVS diode.

[0093] It should also be noted that in various embodiments of the present invention, the first reference level, the second reference level and the third reference level are used to distinguish reference levels, wherein the first reference level, the second reference level or the third reference level may be the same or different.

[0094] Compared with the prior art, the amplifier circuit provided by the present invention can adjust the amplification factor of the input signal of the amplifier circuit through an adjustment module located in at least one of the front-stage circuit, the post-stage circuit or the feedback circuit of the operational amplifier module, so that the amplifier circuit amplifies the energy of the input signal with the adjusted amplification factor and then outputs it, thereby realizing dynamic adjustment of the amplification factor of the amplifier circuit according to the energy of the input signal.

[0095] The technical terms used in the embodiments of the present invention are only used to illustrate specific embodiments and are not intended to limit the present invention. In this article, the singular forms "a", "the" and "said" are used to include plural forms at the same time, unless the context clearly states otherwise. Further, the terms "including" and / or "comprising" used in the specification refer to the presence of the features, wholes, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements and / or components.

[0096] The equivalent forms (if any) of the corresponding structures, materials, actions and all means or steps and functional elements in the attached claims are intended to include any structure, material or action for performing the function in combination with other explicitly required elements. The description of the present invention is given for the purpose of embodiment and description, but is not intended to be exhaustive or to limit the invention to the disclosed form. Various modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the present invention. The embodiments described in the present invention can better reveal the principles and practical applications of the present invention and enable those of ordinary skill in the art to understand the present invention.

[0097] The flowchart described in the present invention is only an embodiment, and there may be various modifications to the diagram or the steps in the present invention without departing from the spirit of the present invention. For example, the steps may be performed in different orders, or some steps may be added, deleted or modified. A person skilled in the art may understand that all or part of the processes of the above embodiments and equivalent changes made according to the claims of the present invention still fall within the scope of the invention.

Claims

1. A laser measuring device, characterized in that: include: A transmitting tube, used for transmitting an optical pulse signal; A transmitting drive circuit, used for controlling the transmitting power of the transmitting tube according to the received driving signal; A receiving tube, used for receiving the optical pulse signal reflected by the obstacle and converting the received optical pulse signal into an electrical signal; an amplifier circuit, used for amplifying the electrical signal from the receiving tube; A controller, used for calculating the distance between the laser measuring device and the obstacle according to the electrical signal amplified by the amplifying circuit; Wherein, the amplification circuit includes an operational amplifier module and a first clamping module, the first clamping module includes a first diode and a first resistor, the first end of the first diode is connected to the receiving tube, and the first end of the first diode is connected to the first input end of the operational amplifier module through the first resistor; The first clamping module is used to adjust the input signal of the first input terminal of the operational amplifier module, wherein, in response to the energy of the electrical signal from the receiving tube being greater than a threshold and the voltage drop generated by the first resistor exceeding the conduction voltage drop of the first diode, the first diode is triggered to conduct, so as to reduce the input signal of the first terminal of the operational amplifier module; The amplifying circuit also includes a second clamping module located on the post-stage circuit of the operational amplifier module, the second clamping module includes: a second diode and a second resistor, one end of the second diode is connected to the output end of the operational amplifier module through the second resistor, and is used to adjust the output signal of the operational amplifier module.

2. The laser measuring device according to claim 1, characterized in that: An input end of the amplifier circuit is connected to a common end of the first diode and the first resistor.

3. The laser measuring device according to claim 1, characterized in that: The first clamping module is located on the front-stage circuit of the operational amplifier module.

4. The laser measuring device according to claim 1, characterized in that: When the signal output by the operational amplifier module is greater than a certain value, the second diode is turned on.

5. The laser measuring device according to claim 4, characterized in that: The amplifier circuit also includes a post-stage operational amplifier module connected after the operational amplifier module, and the second diode is used to limit the signal input to the post-stage operational amplifier module when it is turned on to avoid saturation of the post-stage operational amplifier module.

6. The laser measuring device according to claim 1, characterized in that: The amplifying circuit also includes a third clamping module located on the feedback circuit of the operational amplifier, which is used to reduce the amplification factor of the input signal at the first input end of the operational amplifier module by the operational amplifier module when the energy of the input signal at the first input end of the operational amplifier module is greater than a certain value.

7. The laser measuring device according to claim 6, characterized in that: The third clamping module includes a third diode and a fifth resistor. The third diode is used to be turned on when the energy of the input signal at the first input end of the operational amplifier module is greater than a certain value, so as to reduce the amplification factor of the operational amplifier module on the input signal at the first input end of the operational amplifier module.

8. The laser measuring device according to claim 1, characterized in that: The laser measuring device also includes a comparison circuit and a time-to-digital converter; wherein the comparison circuit is used to convert the signal amplified by the amplifier circuit into a digital pulse signal, and the time-to-digital converter is used to extract the time information of the digital pulse signal and send the time information of the digital pulse signal to the controller.

9. A mobile platform, characterized in that: include: The laser measuring device according to any one of claims 1 to 8; and The platform body, the laser measuring device is installed on the platform body, and is used to measure the external environment.

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